The objective of this proposal is to develop a fundamentally new way to construct heterogeneous functional systems via self-assembly inside living cells. The approach is to fabricate functional inorganic nano-scale components, to microinject them into live cells, and to allow them to self-assemble into an interconnected structure. The self-assembly is driven by and programmed with specific covalent and supramolecular bonds resultant from the interaction of biomolecules (e.g. polypeptides) and inorganic surfaces.
Intellectual merit: The project develops a fundamental understanding of biomolecule/inorganic surface interactions and develops a methodology to use the molecules to self-assemble structures, made from parts originating in incompatible fabrication processes, from the bottom-up. The project pioneers a new paradigm in constructing artificial structures inside live cells and provides a new venue for characterization of live cells from within. This ability is critical in expanding the current understanding of biology and providing a new tool for studying biology at the single cell level.
Broader Impact: One of the main objectives of this project is to train a new generation of engineers that are capable of conducting research at the interface between electrical engineering and biology. This training is provided by their active participation in the research program at high school, undergraduate, and graduate levels and is augmented by development of new courses in experimental nanofabrication, self-assembly, and engineering design of cells. One of the main focuses of the outreach program is to connect with the Native American high school students of the State of Washington and to encourage their active participation in research.
The project enabled the construction and investigation of a number of nano-scale and micron-scale devices. Besides training both undergraduate and graduate students in research, the major outcome of the project was the implementation of ultra-low power circuits and building a direct interface between them and live organisms. We were able to show that circuits that require extremely low power levels in the order of nano watts can be powered directly from their interface with a live organism. We constructed a number of nano-scale objects including nanorods and investigated their directed assembly onto electrically connected substrates using peptide interactions. We investigated the effect of local electric fields on enzyme function by constructing a test set-up that allowed for enzyme immobilization, application of electric field, and measurement of enzyme function. Also, the project resulted in the development of a number of molecular sensors including devices for detecting glucose or lactate that can have important biomedical applications. These sensors are all electroenzymatic and can be integrated onto flexible plastic substrates. The sensors generate an electronic signal upon detection of the target molecule that can be further digitized and used by complementary circuits. The results of the project were distributed through conference and jounral publications and technical presentations.
